Is a 160MB/s CF Card a Good Idea?
Not sure why my reply didn't show up... Let's try again:
The answer is basically: No difference between a 60 MB/s and a 160 MB/s Sandisk card in a 7D. I tested both myself. The results:
1) The camera buffers about 23 RAW images into RAM before writing out to Compact Flash. Card speed here is irrelevant. You get 21-23 frames in 3 seconds, then the buffer is full and fps falls to about 2.
2) After the burst finishes, the 7D writes data to the CF card in about 5 seconds (160
MBs card) and 10 seconds (60 MBs card) respectively. So the faster card makes your camera ready sooner.
3) The faster card probably copies files to the PC faster, but I didn't test this.
My conclusion is that the 60 or 90 MBs cards are fine in the 7D and a faster speed only wastes money. Unless you're like me and you spent the money so you can test the card and warn others not to waste their money.
Thanks, your #2 is what I'm after and is important to me so I went with the faster card. My thought is a card is something you buy every couple of years, it's best not to skimp on it.